how do you Rendezvous?

[SIR DURPINGTION]

can all of my fellow ksp players tell me how to rendezvous in the simplest way? i am new and i want to start building space stations and refueling stations, i have gotten to the mun and minmus but i want to go further And also, with the stock rover it tends to make sharp turns, has anyone else got this problem?

[Warzouz]

Rendez-vous may be the hardest manoeuvre to do. If you're too lost, you can use MechJeb to do it for you and to learn how to do it, even if MJ may no do the most efficient way.

Here is how to do it:

• First launch not too far from your target and try to be in the same plane if you can.
• "Set as target" the ship you want to rendez-vous with.
• Change you inclination (normal or ant-inormal) to match your target. you must do this manoeuvre at ascending or descending node.
• Now you must set a rendez-vous point : your orbit must touch (not intersect) your target orbit.
• If you're behind it, your own orbit should be inside your target's. If your before it, your own orbit should be outside your target's.
• If you're far from your target, wait few orbits to close on.
• When you're near, you need to create a node and tweak it (radial and pro/retrograde, not normal) to line up the intersect marker. Don't forget you can "slide" your node on the orbit.
• When you get a range < 0.5km, you're good. Do the burn and wait to close on your target.
• Switch to target mode and prepare to burn retrograde (relative to your target). Burn until speed is 0m/s
• Optionally you can close on your target, orient to the target and do a light burn.
• Again prepare to retro burn when your near your target to 0 speed.

Rendez-vous is done, now you have to dock.

This resumes it

Edited May 13, 2016 by Warzouz

[bewing]

As far as sharp turns goes ... it's better to tap the turn keys, and not hold them down. If you are going a little too fast and you overuse your keys you can roll your rover over, and that can be a disaster.

Sadly, there is an annoying bug with rendezvous right now.

There are two phases to setting up a rendezvous: 1) orbital maneuvering to create a close approach, and 2) once you have a close approach, then you have to stop the ships next to each other (or perform a docking).

When you have two ships in orbit, you can "target" one from the other. This will give you some indicators that are crucial to rendezvous properly. You use the Ascending and Descending nodes to get your ship on the same plane as the target ship -- by burning a little bit in either the Anti-normal or Normal directions (respectively) at the nodes. Once the ships are in the same plane, the ship that is in a lower orbit will catch up to the ship that's in a higher orbit. It is especially useful if you make the orbits cross just a little bit. The game is supposed to put two "intersection indicators" on your orbit that tell you how far away the target ship will be at the intersection points. The bug is that only one of them usually shows up. But in general, you wait until an orbit where the two ships will approach fairly closely, and then you adjust your Pe and Ap with prograde/retrograde burns until those intersection indicators say your distance will be less than a kilometer or so at that point. And then you wait.

Once you are close, you go into targeting mode on your navball and find the retrograde indicator. If you lock on to retrograde, and burn until your relative velocity is 0.0, then you are stopped right next to the other ship -- all ready to dock.

 

[RizzoTheRat]

The key thing is that to gain on a target you need to slow down, meaning you drop your periapsis, take a shorter path than the target and therefore catch it up.  To have a target gain on you, you need to accelerate, raising your apoapsis and taking a longer path than the target so it catches you.  That seems counter intuitive when you first start.

For LKO it's generally easier to launch ahead of your target as you need to go higher to let the target catch you, if you launch behind it you need to go lower and you might not have much space to do so.

 

[Plusck]

I made an album to demonstrate maximising cash-for-player-time out of "rescue kerbal in orbit of Kerbin" contracts. The first part contains illustrations of a lot of the things people have been referring to in this thread, so it might be useful.

If I had decent recording software, I'd make a video since that tends to be easier to illustrate things, but I don't. Basically all of the relevant info, though, is visible on the NavBall and how that changes as the position and shape of the orbit changes. Viewing the album in full res is therefore recommended...

 

Also to be noted - I never ended up managing to align target retrograde with antitarget on this run. That's because I was making such large changes to velocity on an orbital path that crossed the other, starting at very close quarters (c.200km), that I only really got lined up at the very last moment.

If you start off with much less of a difference in velocity and from further away, then you really must do a better job at "pushing the marble" about an eighth (or slightly less) of an orbit away from the encounter, otherwise you'll miss by miles.

Edited May 13, 2016 by Plusck

[Meithan]

Here's how I do it, using a phasing orbit. It's perhaps not fuel-optimal, but it's not too wasteful either and is much easier than other more fuel-efficient strategies. Works every single time.

1. Launch into an orbit as close to your target's orbit as possible but ahead of your target - the closer you are to the target, the less fuel you'll need to rendezvous, but it's important that you're ahead of it, so being ~30° ahead is ok. This is much easier than trying to precisely hit your target on launch.
2. Wait until the ascending or descending node between your orbital planes and zero out your relative inclination. It's important to closely match the orbital planes only; matching Ap and Pe closely is not necessary.
3. Now simply choose a point along your orbit where you'd like the rendezvous to happen (e.g. in sunlight), set up a maneuver node and pull on the prograde thingy. As you raise the apoapsis of your projected orbit, you'll see one of the close approach markers start to move, go around the projected orbit, and eventually meet the other (which remained at periapsis). Further tweak the maneuver to minimize the closest approach distance and you're set. The point of the this phasing orbit is to have a longer orbital period so that the target (which is behind you) catches up.
4. Perform the maneuver and you'll rendezvous at the next periapsis. You can further fine-tune the closest approach at apoapsis of your phasing orbit.

Hope this helps. I'd illustrate it with diagrams but I'm in a hurry right now. Might do it later.

[Superfluous J]

I've been told this video of mine has helped.

Spoiler

 

 

[Geschosskopf]

17 hours ago, SIR DURPINGTION said:

can all of my fellow ksp players tell me how to rendezvous in the simplest way? i am new and i want to start building space stations and refueling stations, i have gotten to the mun and minmus but i want to go further And also, with the stock rover it tends to make sharp turns, has anyone else got this problem?

Others have already posted all kinds of very useful stuff so I'll just add 1 thing....

All of that technical info and how-to stuff is all very well, but even equipped with all that I struggled myself until I grokked the underlying concept, which I didn't get until after I did a trip to Duna without benefit of docking anything beforehand.

What I'm saying is that basically, rendezvousing and transferring to other planets is the same thing.  Sure, if you're on the ground and your target is orbiting the same body you're landed on, you can rendezvous from launch with proper timing, but that's a special case.  The much more common general case is that you're already in orbit.   And in that case, same as when transferring to another planet, you have to wait for the proper transfer window, which occurs when you and your target have the correct phase angle between them.  So to me, the whole trick of rendezvous is get a feeling for the interplanetary transfer phase angles so you can eyeball them in rendezvous situations.

The whole trick with both rendezvousing and transferring is to put the maneuver node in the right place.  Which means knowing your phase angles.

[mrclucks]

Assuming you're already in an orbit, you first want to align your orbit fairly well from the ascending node or descending node (not actually necessary but its much easier if you do).

Then you want to get an orbit where you can intercept your target at a relatively low speed.  You can do this by having your AP or PE touching the target orbit and playing around with the other end so that you will eventually pass pretty close to your target after a few orbits, or you can get into an orbit outside or inside your target orbit which will help you get close to your target faster.  

Next step is when your next orbit will place you fairly close to your target (~20km for kerbin orbit) you'll want to set up a manuver node to finely adjust how close you will actually intercept and bring it down as close as you can, but 5km is usually the max distance for LKO.  

Once you have that close intercept, you will want to change to target mode and burn retrograde to the target when you get close so your relative speed is low. Once your speed is relatively low you've basically just rendezvoused.  

For docking I typically have the module that I'm docking to have its docking node face the craft that is doing the actual maneuvering.  Then I use RCS and adjust the relative prograde vector align with the target vector while closing the gap between them.  1m/s per 100 m is typically fast enough but can be adjusted depending on how fast the RCS can change my velocity.  Once I reach 50 meters I slow down to .2 m/s .